Modern commercial vehicles contain air supply systems which are used to power air systems, such as service brakes, windshield wipers, air suspension, etc. Typical supply systems utilize an engine mounted and driven air compressor. The compressor delivers air to an air dryer. The air dryer filters, cools and dries the air. The air is delivered to one or more reservoirs. The systems draw the air from the one or more reservoirs.
Typically, the air supply system pressure is controlled by a pneumatic governor. The governor monitors the reservoir pressure, and uses air from the reservoir to signal the compressor and the air dryer. Typical air supply systems operate based solely on the reservoir pressure that is sensed by the regulator. When the system pressure falls below a lower predetermined value, such as 100 psi, the governer activates the compressor to begin increasing the pressure in the air system. The compressor builds air pressure until the air system pressure reaches an upper predetermined value, such as 125 psi.
U.S. Pat. No. 6,682,459 (herein “the '459 patent”) assigned to the owner of the present invention discloses an electronic air charge controller for a commercial vehicle air brake system. The '459 patent discloses pausing the air compressor charging cycle when a high load condition is encountered. The '459 patent also discloses increasing engine speed when the vehicle is parked and the air supply is recharging to reduce the amount of time required to charge the air supply system. The '459 is incorporated herein by reference in its entirety.
Richard Conklin & Bill Hudgins, Electronic Compressor & Air Dryer Control, ASE 1999-01-3771 (1999) (herein “ASE article 1999-01-3771) contemplates electronic control of a pneumatic charging system of an air braked vehicle. ASE article 1999-01-3771 is incorporated herein by reference in its entirety.